VXLAN is a network virtualization technology that provides layer 2 overlay on a layer 3 network by encapsulating Ethernet payloads in Internet Protocol (IP) and User Datagram Protocol (UDP) (IP/UDP). Border Gateway Protocol (BGP) Ethernet Virtual Private Networks (EVPNs) May be used as a control plane for VXLAN overlays. Network Virtualization using Generic Routing Encapsulation (NVGRE) is another network virtualization technology that also provides layer 2 overlay on a layer 3 network by utilizing Ethernet encapsulation in IP.
When unicast replication at a head end is in use, multi-destination traffic is encapsulated in a unicast VXLAN Tunnel Endpoint (VTEP) IP address. Multi-destination traffic typically includes broadcast, unknown unicast, and multicast traffic. As a result if the encapsulation of multi-destination traffic, duplicate packets may be delivered to an end station. Similarly, when EVPN is used as a control plane with VXLAN encapsulation, duplicate packets may also be delivered to an end station. The inability to distinguish a difference between a known unicast packet and a unicast head end replicated packet resulting from an unknown unicast in a VXLAN header causes duplicate packets to be delivered to an end station.